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Posted by: freestone Sep 1 2003, 05:23 PM

For a 3.2 conversion, to be used almost primarily on the street do you think I need a roll cage? 95% on the street, easily.

I would use this car maybe 5 days on the track though, as I race vintage, but loading up the race car and bringing it to the track etc is such a production and an expensive engine that I skip some lap days when I would bring more of a street car there?

I really don't like the way they look frankly. And I am 6'2" so worry about clearance. Wonder if a helmet would clear?


Is a supplemental roll bar worth it?


And have people gotten in trouble in 914-6's? They sit so low too I worry about the SUV's hitting me. Does anybody think this makes a difference, as getting hit is not exactly the same as rolling, and I wouldn't do the door bars.

And I really care about safety, but the cosmetics of a cage get me down a bit.

Thanks,

Posted by: URY914 Sep 1 2003, 05:34 PM

Unless you're going to wear a helmet and use a harness, I won't have a roll cage in a 95% of the time street car. That would mean you are 95% more likey to get in an accident on the street than on the track.

Try hitting your head on those bars when you get rear ended at 10 mph.

If your worried about an SUV hitting you, you better buy an SUV. Does everyone driving a small car worry about SUVs?

Paul

Posted by: serge914 Sep 1 2003, 07:00 PM

I have mostly the same concern; driving with a race seat and 5 points seat belts but no bar, I wonder what would happen if I flip the car on a race track. I can't move my body aside and wonder if the targa bar can hold the weight of the car.

Posted by: freestone Sep 1 2003, 08:01 PM

Would a roll bar help at all? On a track, you need to have it tall enough that if you draw a line from the roll bar to the fender it clears your helmet by 2". That would probably make it too tall to use the top?

I heard the GT top was reinforced; I assume that is just for rigidity.

Can a subtle but effective roll bar be created?

Posted by: Qarl Sep 1 2003, 08:20 PM

What about a street bar as a compromise?


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Posted by: campbellcj Sep 1 2003, 08:51 PM

Honestly, in a street car I would rather have the door bars and the side-side + front-back bars, than the overhead roll hoop(s). The odds of rolling the car in even aggressive street driving are super slim, unless you go off an embankment or something. You are much more likely to get cut-off or t-boned. Getting hit in the doors is a terrifying thought, since the teener sits so low and has minimal door & roof strength.

Posted by: J P Stein Sep 1 2003, 09:05 PM

I put a cage in my car to stiffen the chassis....it mounts at 10 points. One of these days I'll run 4 tubes to the shock towers to strenghten things more throughly.

As it is now, the front and back ends move in concert rather than independently.

I don't drive it much on the street. Being rammed by a Broncosaurus would riuin my day.....helmet or no.

Posted by: JmuRiz Sep 1 2003, 09:05 PM

Chris,
I was thinking the same thing. An added benefit of having all the 'under the windows' tubing of that style of cage would give you the same look of openness while streetdriving w/ the top off. Has anyone tried this before? I think it'd be a great idea!

Posted by: freestone Sep 1 2003, 09:36 PM

I agree about my fear of getting hit in the sides.

I added door bars in my race car for worry about getting broadsided if I spun.

I suppose a cage without the door bars at least protects you against a side hit that isn't perpendicular, almost.

But door bars are so obtrusive as you have to climb over them, much more so than a cage.

That's the big advantage of modern cars, like the Boxster. And those crumple zones and air bags etc.

I drive a 356 roadster around on the streets, and that is a worry too.

Posted by: airsix Sep 1 2003, 09:41 PM

Like JP said. And remember that picture posted last week of the white 914 that was in a front-end colision and folded in half like a taco right about where the heater tubes go through the longitudinals at the rear firewall? Good cage would have stopped that.
-Ben M.

Posted by: Steve Sep 1 2003, 10:03 PM

I have an Autopower roll bar in my street 914.
Mine is the updated one thats welded to the side longitudinals instead of the floor pan.
I also have the bolt in cross bar that goes to the floor for mounting a video camera.
Can't wait to try it.
I'm also running the welded in steel plates in the rear.
The steel plates weld onto the side longitudinals.
Is anyone running the full Autopower roll cage?
Do the window winders still work with the doors closed?

It would be nice to have a full cage in case of an accident with an SUV or drunk driver.
It would be better than nothing.

Steve

Posted by: Qarl Sep 1 2003, 10:09 PM

Steve.. can you post some pics for us all here?

Thanks!

Karl

Posted by: J P Stein Sep 1 2003, 10:33 PM

My cage is an Autopower....with door beams. The beam is extended to a doubler plate mounted on the sides of the footwell where the speakers mount.
Getting in & out is a PITA......and neck, when I have a helmet on.

I deleted the cross bar on the roll bar & the diagonal
from the top of the bar to the floor.

I'd have to take new pics if you want to see details.
Just ak me.

Posted by: Qarl Sep 1 2003, 10:38 PM

I hate this frigin emoticon... but here goes...

Posted by: J P Stein Sep 1 2003, 10:55 PM

Ok, I need new pics nohow


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Posted by: J P Stein Sep 1 2003, 10:56 PM

2 of 4.....don't ask bout that lower weld, K?


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Posted by: J P Stein Sep 1 2003, 10:56 PM

3 of 4


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Posted by: J P Stein Sep 1 2003, 10:57 PM

4 of 4- Aren't digital cameras wonderful?


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Posted by: ChrisReale Sep 1 2003, 10:58 PM

JP, is your cage this one?
http://www.ioportracing.com/Merchant2/merchant.mv?Screen=PROD&Product_Code=60080D&Category_Code=AP080

Posted by: seanery Sep 1 2003, 11:03 PM

mine is. got no pics of it though.

Posted by: J P Stein Sep 1 2003, 11:06 PM

I did get it from I/O Port. The drawing is not very accurate tho. It's more like the U- weld jobbie.
It had a removable (bolted) cross brace on the roll bar, but the upper attach point was too close to my haid.....outta here. I never mounted the diagonal brace to the floor.....takes up room for the pass.

Posted by: ChrisReale Sep 1 2003, 11:08 PM

Did you weld it in yerself?

Posted by: J P Stein Sep 1 2003, 11:14 PM

Nopers.....the guy down the street is a pro. I did the lower weld cause he's 280 lbs & we had a fitment problem......I'd have done better with a soft hood....really! I still have bruises from that operation.

Posted by: J P Stein Sep 1 2003, 11:27 PM

The plates that are welded to the longs were fabbed as were the plates at the rear bottom and kick pannels.
I didn't think much of their method of attachment to the longs.

This job was a major PITA. Tony C's cages look much better and the front legs are set foward more giving more entry room. The cross bar under the dash barely has clearance for my knees. I'd prolly loose both kneecaps in a big front hit......who needs em'?

Posted by: seanery Sep 1 2003, 11:37 PM

If I were to do it again, TonyC would be my choice. Fitament is/was a major PITA.

Posted by: J P Stein Sep 1 2003, 11:40 PM

Posted by: Steve Sep 1 2003, 11:48 PM

Here's some pictures of just the roll bar.
The welds are the same as JP Stein


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Posted by: Steve Sep 1 2003, 11:48 PM

Picture #2


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Posted by: Steve Sep 1 2003, 11:49 PM

Picture #3


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Posted by: J P Stein Sep 1 2003, 11:52 PM

Hay, Steve, I like them seats. What model ? Gud mounts?.....yada.

Posted by: Steve Sep 2 2003, 12:31 AM

My seats are a love hate relationship.
The seats are made by Corbeau.
The model is Forza
They only cost $225 a piece brand new.
The 914 adapters are $20 a piece.
They are very comfortable and if you remove the seat pad there about the same heighth as stock.
I sliced a 1/4" piece of the foam out of the seat pad to create the stock heighth and still be comfortable.
The high bolsters are great for cornering.
Now the down side.
-The top is very wide and creates blindspots when driving on the street.
-The high bolsters makes it hard to get in an out for a daily driver.
-The seats will not go back into the backpad.
No problem for me since I'm only 5"10" and I don't need the seat all the way back anyway.
I'm currently reupholstering the stock seats for daily driving.
I will probably keep one of the Corbeau's for autocrosses and sell the other one.

Steve

Posted by: Brad Roberts Sep 2 2003, 12:43 AM

I have little experience in this area..

Steve.. I hate to tell you but that bar going down is close to worthless. The floor is not strong.

JP ?? why all the dam padding ?? Hitting your head on the passenger side bar is going to be tuff to do..LOL

Tony does a awesome street cage that functions very well. The door bar is just above the frame rail and angles up right where the seat starts up.

I still have no idea how or why you guy's think you can hit your head on the tubes ?? The rear hoop is far above my head (6'1) and the front main hoop is too far away when you have the seat one click forward from all the way back. The only bar that I think about is the one to the side of my head. I honestly dont think anyone making the comment has sat in a car with a full cage. There is NO way your racing harness is going to allow your head to hit the front halo/hoop.

Here is one way to the do the race bars..

B

Posted by: Brad Roberts Sep 2 2003, 12:44 AM

Here is one street bar..


B

Posted by: Brad Roberts Sep 2 2003, 12:44 AM

Here is another...

B

Posted by: URY914 Sep 2 2003, 05:49 AM

Now if we can get back to the original question.

Putting a full cage in a car that will be driven 95% of the time is not worth the PITA factor.
1. It will look like crap. Bars wrapped with padding is not a nice detail.
2. It will be a PITA getting in and out.
3. You're reducing the size of the interior.
4. If you doing this because you worry about SUVs, you shouldn't be diving it anyway. Buy an SUV.

You can add a roll bar hoop and run some low side bars that will add some stiffness to the car. But you are really just improving the car at its weak point.

A car designed in the sixties will not protect you when hit by a 2003 Ford F150 no matter what you do to it.

What I'm saying is if safety is your #1 concern, you maybe need to think about driving a different car 95% of the time.

Paul

Posted by: Don Wohlfarth Sep 2 2003, 07:14 AM

The cabin in a 914 is surprisingly strong. BTDT
With a 95% street car I would not put a cage in it. It is a major PITA getting in and out if the cage is done correctly.
If you have race seats it will be almost impossible to get in and out without a removable steering wheel.
It intrudes on cabin space.
It is a PITA to wear a 5 point harness anytime you drive the car. The good news is the harness will keep you in place. The bad news is the harness will keep you in place. If you can move while wearing the harness it is not tight enough.
If you don't have side impact protection you might as well have none. It's similar to being pregnant, either you are or you're not.
The webbing on belts/harness will stretch.
Depending what group you run with, they may not allow the car on the track without a cage. In PCA the motor would put you in GT 3, a long way from installing a 2 liter in place of a 1.7.
If you're going to the expense of installing a cage do it correctly. I would tie in the suspension points as well.

Posted by: ArtechnikA Sep 2 2003, 08:08 AM

Posted by: JmuRiz Sep 2 2003, 10:40 AM

Brad,
That's the picture/style i was looking for! Who made that cage? Those side bars and the ones under the dash and behind the seats would make a great street cage! Thanks for any info on it.

Posted by: Racer Sep 2 2003, 10:46 AM

Freestone,

Was the 3.2 necessary? my guess is not. So, why would a cage be necessary? Sure it will add weight to the car, but it will add structural support as well, at the cost of some interior room and ease of enty/exit. As mentioned, where will your other "5%" be used? will they require you to have a roll cage? I think you know what your budget/conscious is saying...

ps- I like my cage!

Posted by: Britain Smith Sep 2 2003, 10:59 AM

Posted by: Brad Roberts Sep 2 2003, 11:27 AM

Yeah. Those bage builders are hard to come by.

I agree about the getting in out of the car with the cage and high bolster seats. But honestly it isnt that bad even with the X brace.

I also agree about the need for a removable wheel (even in a normal street car).

Jimmy, (still love the avatar)

The only way to do a cage and make it liveable on the street is to do it under the dash. This keeps the knee bar away from you and really opens up the interior. When driving the car.. you will semi forget you have cage. The only bar that really shows is the windshield halo (and Tony has a new design that fits the winshield tighter).

95% street: Weld in some stiffening and I dont mean chassis GT stiff kit.


B

Posted by: PatW Sep 2 2003, 01:18 PM

Posted by: Brad Roberts Sep 2 2003, 01:22 PM

Robs bar is removable. But just like all removable bars.. the owners never actually remove them.

Robs bar is totally livable on the street. I dont really care about my passengers comfort.

The bar in Robs car made a hell of a difference in the strength of that tub. Its all about the placement of the down tube. We took it to a very strong area on the car (inner wheelhouse corner of frame rail) and NOT to the floor. It is far enough forward that it doesnt freak passengers out sitting behind it.


B

Posted by: PatW Sep 2 2003, 01:33 PM

I rode in it and I liked it. Wasn't that bad after I learned how to sit down into it. Ya, hella stiff. I could tell that its quicker on the turn on compared to my stocker.

On the list for wanna/gotta have it.

Posted by: maf914 Sep 2 2003, 01:48 PM

Brad,

[QUOTE]95% street: Weld in some stiffening and I dont mean chassis GT stiff kit.

What stiffening are you referring to, if not the GT kit?

Mike

Posted by: synthesisdv Sep 2 2003, 02:21 PM

We really beefed up our main hoop mount at the firewall\rocker intersection. The plate wraps around the horizontal and vertical surfaces of both sections. Also moved the FI ECU inside.

The rear supports required a lexan window for passthru. The bend in the bar was necessary to allow the stock lid to funtion normally.

The front mount plates are up against the inside wheel wells. This adds support to the forward section of the car and will help keep a wheel from being pushed into the cabin which is a common failure in a major front quarter imapact.

Our doorbars are as far to the outside as was possible. We left about .25" for the padding. The horizontal bar is up under the dash to keep it away from our shins and lower legs.

Our rear supports attach to the forward part of the rear wheel wells. Our vintage class does not allow tying into the suspension pickup points but this could easily be done later if we progress to a production class.

The seat back brace only had to be about 1.5" long.

I had a pretty good idea what I wanted before we started the cage. Even with all the extras the car is less than 1900 lbs with the full steel body and steel bumpers. All the glass is lexan and that helped with the weight alot.

I wouldn't track the car without a cage under any circumstance.

regards,
dr


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Posted by: Steve Sep 2 2003, 02:33 PM

Posted by: SirAndy Sep 2 2003, 03:10 PM

Posted by: Brad Roberts Sep 3 2003, 12:48 AM

DR..


Please tell us about that carbon fiber skin for a passenger door ?????


And tell me your name.. I dont know if DR is Doctor..or Dave Ranchero ??



B

Posted by: Brad Roberts Sep 3 2003, 12:53 AM

Mike,

Your can strengthen your frame rails by adding one or two of the following:

1. outside clam shell behind rocker from Restoration design
2. Brad Mayeur clam shells (more for rust repair)..but you get the same effect..they are crude however compared to the form fitting of no. 1. on the list.
3. weld flat steel in a U shape from one side to the other on the INSIDE of the tub. It all gets hidden with carpet when you use 16 gauge. The U shape starts at the bottom of the fenderwell and wraps all the way around to the other fenderwell. You can weld it on every few inches. It takes some work to get around the E-brake setup.. and to get over the center tunnel on the firewall... but it works MUCH better than No. 1. and No.2 because you have now tied both sides of the car together with a very strong piece (lower firewall).


B

Posted by: synthesisdv Sep 3 2003, 05:52 AM

brad,

the door panel was laid up from 5.7oz twill CF cloth with epoxy resin. The layup was done on a large sheet of glass to achieve a smooth finish. I have some experience working with fiberglass but this was my first CF project. What I found out is that a part this large needs more than one layer of CF cloth or at least an additional layer of fiberglass behind. It came out too flexible but looks pretty good. Right now it is only attached to the door with heavy duty velcro.

Also, I did not care for the epoxy resin from US Composites. It is there own label and took an eternety to harden. I used the correct ratio and mixed the hardener before combining with the resin but it just never seemed to cure well. I will use West System next time. It worked for me in the past. More $$$ but worth it.

I plan on fabricating dash panels next from CF and then some various brackets.

thanks for the interest,

(dr) david rosenbloom

Posted by: maf914 Sep 3 2003, 06:35 AM

Brad,

Thanks for the info. I was aware of the clam-shell reinforcment approach, but had never heard of the inner frame reinforcement. Sounds like a good idea.

So with these arrangements do you think the GT stiffening kit, which adds the reinforcing plates behind the cockpit tub, is not really necessary for a street car?

Mike

Posted by: Brad Roberts Sep 3 2003, 01:01 PM

Thanks David. My CF experience is very limited.. but I'm highly insterested in learning about it. You car turned out very nice. Quality work.


Mike,

I do not feel the GT stiff kit is needed unless you are running springs rates in the rear over 225lbs. and plan on racing the car (alot). The reason the GT kit even exists..is because the shock tower tries to rip off the end of the frame rail. It does this because of excessive loading of that area (bigger springs and racing). the GT kit tries to stiffen this on the OUTSIDE of the frame rail next to the shock tower. Worthless... it will still crack and break under racing conditions and high spring rates. Its a band-aid for a bigger problem.


B

Posted by: andys Sep 3 2003, 02:55 PM

Posted by: Brad Roberts Sep 3 2003, 03:01 PM

Down tubes from a main hoop to the tops of the shock towers. Much like the pic above. Which all race cars should have anyway. You can do this without a main hoop. Weld a piece of square tubing across the engine compartment firewall right below where the engine lid mounts. Again.. tie both sides of the car together and weld tube from the sqaure tube to the front side of the shock towers where the frame rail meets the front of the shock tower. These two tubes would be out of the way on most cars and they dont have to be real big. I dont have a good pick of this setup done..

Weld the sqaure tube here across the car. The take tubes to the same location you see the tubes in this pic.


B

Posted by: Brad Roberts Sep 3 2003, 03:04 PM

dfgsfdg

Posted by: Brad Roberts Sep 3 2003, 03:06 PM

Like this.


B